Significance

Recent archaeological discoveries on the south coast of Peru demonstrate that Paracas period peoples constructed a complex set of geoglyphs to mark ceremonial mounds and residential sites. Paracas societies in this region created a built or artificial landscape in an open desert to mediate periodic social events. Several of these architectural features were oriented to the sunset during the winter solstice. These data provide insight into the ways by which people in stateless societies organized their social, economic, and political life. Social units, labor, and astronomically significant periods mesh, attracting participants to cyclical events in the midvalley zone. This case study refines our understanding of the processes of human social evolution prior to the development of archaic states.

Abstract

Recent archaeological research on the south coast of Peru discovered a Late Paracas (ca. 400–100 BCE) mound and geoglyph complex in the middle Chincha Valley. This complex consists of linear geoglyphs, circular rock features, ceremonial mounds, and settlements spread over a 40-km2 area. A striking feature of this culturally modified landscape is that the geoglyph lines converge on mounds and habitation sites to form discrete clusters. Likewise, these clusters contain a number of paired line segments and at least two U-shaped structures that marked the setting sun of the June solstice in antiquity. Excavations in three mounds confirm that they were built in Late Paracas times. The Chincha complex therefore predates the better-known Nasca lines to the south by several centuries and provides insight into the development and use of geoglyphs and platform mounds in Paracas society. The data presented here indicate that Paracas peoples engineered a carefully structured, ritualized landscape to demarcate areas and times for key ritual and social activities.

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